Heretofore, various analyzers for automatic analysis of human blood have been developed. Such analyzers greatly differ in analyzable concentration ranges for different items to be analyzed (for example, from mg/ml to pg/ml). Depending on respective items to be analyzed, different analyzing methods (measuring principles) have been selected from, for example, an enzyme immunoassay (EIA) method, a latex immunoassay (LIA) method, a turbidimetric immunoassay (TIA) method, and a fluorescence immunoassay (FIA) method, a chemiluminescent enzyme immunoassay (CLEIA) method in consideration of the concentration of the objective substances. Furthermore, there are items to be analyzed, for which a sample in the form of an undiluted solution is measured as it is, and there are also items to be analyzed, for which dilution of a sample is needed prior to measurement of the sample. Recently, instruments which can cover a plurality of kinds of items to be analyzed and a wide range of concentration by themselves alone have come to be developed.
However, in the aforementioned instruments which perform multi-item processing by themselves alone, although a sample-dispensing device, a reagent-dispensing device, a reaction well, etc. are shared, several kinds of modules corresponding to the measuring principles are integrated in a single instrument, thus making the instrument to have a very complicated mechanism and be a large-scaled one. The complicated mechanism leads particularly to an increase in the number of operating parts, which naturally results in an increase in trouble such as breakdown. Thus, daily maintenance and inspection as well as management of the precision of the instrument become a big load. In addition, different measuring principles will naturally require different analysis processes for controlling the amount of a sample, the kind of a reagent, the amount of a reagent, the condition of stirring, the condition of separating a reaction product and an excess reagent from each other (B/F separation), the reaction time, the measuring method, etc. depending on the respective items to be analyzed. It is essentially impossible for a single instrument to perform a plurality of different analyzing processes concurrently; under the present circumstances, progress of individual analyzing processes is strictly controlled so that different analyzing processes should not interfere with each other. Therefore, in the case where samples whose items to be analyzed differ from each other are to be concurrently measured, waiting time (waiting state) is required, which leads to a decrease in throughput capacity, which is a cause of a considerable increase in time required for measurement.
In addition, two to six kinds of reagents are to be used for each item for analyzing, in general. This imposes a great load to the operator in preparation before measurement.
In summary, in the conventional instruments, the complexity of their mechanism increases the load of their maintenance and production cost thereof, as well as the time required for measurement and the time and manpower for preparing necessary reagents. These become big problems particularly, for example, in emergency testing and in point of care testing (POCT) that physicians/nurses perform.
To cope with such problems, a “one test-one cartridge” type cartridge for automatic measurement having filled with all the reagents necessary for measurement in the form of solutions, respectively, has been proposed (JP 11-316226 A). However, no method for coping with different dilutions, which will be required depending on items to be analyzed, has been proposed yet.